There are known cleaning techniques that involve high temperatures that may be detrimental to the particular equipment or that involve powerful chemical reagents such as oxidants like peracetic acid that also adversely affect not only the primary medical devices but also the equipment used to clean the devices.
It is well known that transient supramolecular organisation of amphoteric molecules form micelles. The transitional quality of such organized groups is believed to provide an explanation of the enhanced activity of microbiocides when combined in certain cleaning preparations as reported in literature.
There is a known detergent action, namely the gathering together of surfactant molecules to form micelles. Such micelles are also alluded to in known theories explaining the observed biological action of cationic biocides such as quaternary ammonium compounds. Molecules of this type interact fleetingly with the phospholipids and peptidoglycan parts of cytoplasmic membranes of micro-organisms, which interaction causes these membranes to become disturbed and then to explode, leading to the death of the cell.
Up to the present time, an overabundance of inventions for preparations for disinfecting and sterilising materials and surfaces contaminated with bacteria and bacterial spores have come about through empirical observations of biological action.
All of these inventions require some form of microbiocidal fluid which is brought into contact with the contaminated material or surface long enough to be able to disinfect and sterilise said contaminated material or surface.
Prior Art provides several cleaning preparations as follows:
Baugh et al. U.S. Pat. No. 6,656,919 describes a microbiocidal solution which can range from a simple solution of a single component such as aqueous formaldehyde to complex mixtures of microbiocides and various adjuncts including microbiologically active components such as germination promoters or other inert material that displays surfactant properties. The microbiocidal properties of cationic surfactants such as quaternary ammonium compounds (QAC) and biguanidinium salts are well known and authenticated.
Spooner et al WO9820738 describes microbiological activity which was found to be enhanced when bis(biguanide) microbiocides were combined with polymeric biguanides in contact lens cleaning solutions.
Van Buskirk et al U.S. Pat. No. 5,856,290 describes the combination of QAC and N-alkylpropylenediamine microbiocides with a mixture of non-ionic surfactants which was observed to lead to a noticeable improvement in microbiocidal efficacy.
Lehman et al U.S. Pat. No. 4,920,100 describes bactericidal alcohols and carboxylic acids which were also observed to demonstrate potentiated effects when mixed with certain non-ionic surfactants.
Biermann et al U.S. Pat. No. 4,748,158 describes potentiation in dental cleaning applications of mixtures of chlorhexidine salts and alkylpolyglucosides.
Toshuki et al JP57009717 describes synergistic germicidal activity in mixtures of chlorhexidine salts or polyhexamethylenebiguanide and polyoxyethylene alkyl ethers in the proportions 1:1:W3 which has been reported.
EP05252443.6 suggests the formation of a transient intermediate to explain the observed improvement in minimum inhibitory concentration data for chlorhexidine salts when mixed with various non-ionic surfactants, and until that time a mechanism explaining the origin of such improved microbiocidal efficacy had not been defined.
U.S. Pat. No. 6,303,557 uses biocides and surfactants which differ from those of the present invention, does not include the aliphatic alcohol and requires the presence of sequesterants and amphoteric surfactants to achieve its enhanced microbiocidal activity.
Moreover, there are known U.S. Pat. Nos. 6,814,088, 7,082,951 and 7,094,741 which are for aqueous compositions for treating a surface. However said patents are for preparations which afford superior filming/streaking and shine retention whilst providing disinfecting/antimicrobial benefits. The preparations/compositions of said patents are different from that of the present invention inter alia in that they exclude the component QAC (Quaternary Ammonium Compound), being a cationic microbiocide, which is an essential component of the present invention.
Another known U.S. Patent is U.S. Pat. No. 7,166,563. Said patent is different from the present application as it differs in that QAC are absent from the mixture which may contain PHMB and APG together with other components not used in the present invention.
As noted from the above, none of the above Prior Art gives a solution for the most efficient cleaning, sanitising and sterilising preparations.
It has been observed in some formulations that the activity of particular microbiocides is compromised and considerably diminished by the presence of certain surfactants. It is the recognition of such behaviour by means of empirical observation and the subsequent development of an explanatory theorem which has brought about the formulation of the present invention.